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.global asm_save_all
.global asm_load_all
.global asm_load_mem
stack_backup:
.space 2048
sp_backup:
.space 2
backup_cookie:
.space 2
asm_save_all:
dint
.irp reg,4,5,6,7,8,9,10,11
push r\reg
.endr
mov #1234h, r10
mov r10, &backup_cookie
mov r1, &sp_backup
mov #1c00h, r10
mov #stack_backup, r11
save_sram_word:
mov @r10+, 0(r11)
add #2, r11
cmp #1c00h+2048, r10
jlo save_sram_word
pop r11
pop r10
add #12, r1
eint
ret
asm_load_all:
dint
push r11
mov &backup_cookie, r11
cmp #1234h, r11
jeq do_load_all
pop r11
eint
ret
do_load_all:
; restore SRAM from backup
mov #stack_backup, r10
mov #1c00h, r11
load_sram_word:
mov @r10+, 0(r11)
add #2, r11
cmp #1c00h+2048, r11
jlo load_sram_word
; restore stack pointer
mov &sp_backup, r1
; restore registers
.irp reg,11,10,9,8,7,6,5,4
pop r\reg
.endr
eint
; The return address on the stack has been restored from FRAM backup
; -> execution will continue where asm_save_all was called
ret
asm_load_mem:
dint
push r11
mov &backup_cookie, r11
cmp #1234h, r11
jeq do_load_mem
pop r11
eint
ret
do_load_mem:
push r10
push r9
; restore SRAM from backup, excluding current stack frame
mov r1, r9
sub 6, r9
mov #stack_backup, r10
mov #1c00h, r11
load_sram_word2:
mov @r10+, 0(r11)
add #2, r11
cmp r9, r11
jlo load_sram_word2
pop r9
pop r10
pop r11
eint
ret
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